1. Field of the Invention
The present invention relates to firearms and, more particularly, to the stock/chassis components of firearms and, even more particularly, to a replacement chassis stock system for use with a firearm (e.g. an M-14 rifle) to improve its shooting accuracy, to enhance its ergonomics, and to supplement its functionality.
2. Description of the Background
The technology of firearms is advancing, and it can be very beneficial to incorporate technological advances to improve shooting accuracy, ergonomics, and/or overall functionality. Indeed, the original design of a weapon system often requires updating in order to prolong its useful life. Of course, it is always more economical to update the design of an existing firearm, as opposed to developing a completely new weapon system. This is especially true when many thousands of units already exist, and a retrofit solution can offer significant cost savings to any organization possessing a large number of those firearms in its inventory.
The present inventor is not the first to pose a solution for improving the accuracy, ergonomics, and/or functionality of an existing firearm design. For example, a device for improving an existing firearm's accuracy is found in U.S. Pat. No. 5,412,895 to Krieger, a device for improving an existing firearm's ergonomics are found in U.S. Pat. Nos. 5,970,642 to Martin and 5,711,102 to Paster et al., and a device for improving an existing firearm's functionality are found in U.S. Pat. Nos. 6,499,245, 6,490,822, and 5,343,650 to Swan.
More specifically, U.S. Pat. No. 5,412,895 to Krieger discloses a floating gun barrel mount having the barrel free to remain straight and free of deflection by the sling because it is not attached to the forearm, and a two piece barrel nut to allow universal alignment of gas tube openings. The two-piece barrel nut allows for mass production of the barrel nut, allows alignment for any rotational position of the threads on the barrel receiver, and still provides the high amount of pressure required to secure the barrel firmly to the receiver.
U.S. Pat. No. 5,970,642 to Martin discloses an ergonomic adjustable gun stock having an elongate forearm portion with a longitudinal concave receiver channel in its upper surface for receiving the barrel of a gun, a butt portion extending rearwardly from the forearm portion, a vertically adjustable cheek piece, a longitudinally adjustable and removable auxiliary hand gripping element on the underside of the butt portion, and an adjustable recoil butt pad assembly mounted on the rear end of the butt portion. The cheek piece is an inverted generally U-shaped member having a rounded top surface and contiguous laterally spaced parallel sides. The butt portion has a cheek piece receiving recess sized and shaped to slidably receive the cheek piece in a lowermost position, such that the outer periphery of the cheek piece is generally flush with the outer periphery of the butt portion in its lowermost position.
U.S. Pat. No. 5,711,102 to Plaster et al. discloses an integral user configurable sniper rifle stock comprising a wide forearm and a relatively narrow carry portion extending rearwardly from the forearm. An action mounting portion extends rearwardly from the carry portion. An angled relatively vertical, stippled grip extends rearwardly and downwardly from the receiver portion. An open rear stock portion extends rearwardly from the grip. The rear stock portion comprises upper and lower braces with a butt extending vertically between rear extents of the braces. The upper brace receives a mounting screw for a displaceable, interchangeable cheek piece disposed about the upper brace. A vertically displaceable butt plate/pad and spacers are mounted to the butt. The spacers are used to adjust the length of pull of the rifle.
U.S. Pat. Nos. 6,499,245 and 6,490,822 to Swan disclose a universal receiver sleeve attached to the top of a firearm upper receiver and extended forward above the firearm barrel to a position just short of the firearm front sight. The underside of the rear portion of the sleeve is fixedly attached to the receiver top. The underside of the forward portion of the sleeve has an upper handguard piece attached thereto. A bottom handguard piece is fitted about the bottom of the gun barrel and is attached to the upper handguard piece. The handguard pieces are not physically connected in any way to the gun barrel. The sleeve is self-supported by the connection of the rear portion underside to the receiver top. U.S. Pat. No. 6,499,245 further discloses a special yoke inserted about the barrel nut of the firearm to which the modular sleeve is attached. The special yoke reinforces the modular sleeve while keeping the firearm barrel free floating.
U.S. Pat. No. 5,343,650 to Swan discloses an extended rigid interface frame with upper and lower rails joined to a firearm receiver and extending forward above the firearm's barrel to a head assembly replacing the firearm's normal front sight. A weaver type interface return portion is provided below the barrel from the head assembly to the receiver. A yoke braces the extended rigid frame receiver sleeve of the present invention to the forward portion of the firearm's receiver. The distal end of the extended rigid frame receiver sleeve terminates in the front sight housing that connects the upper and lower rails, thereby providing a housing for advanced laser and sensor components and the standard front sight bead. The front sight housing is self supported by the connection of the upper and lower rails running back to the yoke and secured to the top of the receiver. The barrel of the rifle is free floating in that it does not touch the extended rigid frame receiver sleeve in any manner.
Thus, while a variety of different means for improving the accuracy, ergonomics, and/or functionality of an existing firearm design are known, none of the foregoing devices improve the shooting accuracy of an existing firearm by facilitating the free float of a significant portion of the front end of the barrel and gas system, and enhance the ergonomics via multiple dimensional adjustments of its user interface. Moreover, the above-described devices do not hold the mounting bracket(s) or rails in alignment with the barrel's bore axis and, therefore, lack the ability to maintain proper alignment of any auxiliary devices mounted thereon. Consequently, it would be greatly advantageous to provide a replacement chassis stock system for a rifle that (1) improves the shooting accuracy of an existing firearm by introducing a novel mounting apparatus for the barrel and gas system that facilitates the free float of a significant portion of their front ends, (2) enhances its ergonomics via a fully adjustable buttstock assembly, and (3) supplements its functionality by holding its barrel in alignment with up to five Mil Std 1913 pattern mounting rails.